Flanges: steel, flat, welded, reciprocal, vorotnikovy, corrosion-proof.
Flanges are intended for connection of separate parts of the pipeline and podklyucheniyak to them various equipment. Flanges in the form of separate details most often weld or screw on the ends of the connected details.
Corrosion-proof flanges — pair connecting elements of a trudoprovod from stainless steel with evenly located openings for a coupler fixture of A2 or A4 (bolts, nuts, hairpins etc.). The form of a sealing surface of a flange in pipelines depends on pressure in the pipeline, a profile and material of laying
On a design flanges are the flat disks or rings from high-quality steel having evenly located openings for bolts and hairpins. Such arrangement of openings on flanges serves as a guarantee of nadezhnostigermetichny connection of pipes and pipeline fittings, accession them to devices and capacities, and also for connection of shaft and other rotating details. It is necessary to pay attention that flanges steel are used in pairs, i.e. sets.
Now application to flanges steel was found practically in all industries where pipeline systems, for example, in gas pipelines, oil pipelines, water supply systems and t of the item are necessary. Huge advantage of flanges is that they can be used at any ambient temperature
Flanges can be classified on:
• to design features (flanges steel flat welded, flanges steel welded end-to-end, flanges plug-in free on a welded ring);
• to technological features (depending on material of which they are made);
• to systems of connection among themselves;
• to diameter of conditional pass;
• abilities to maintain various pressure (to 1,0 MPas 10 kgfs/cm2 and from -40 °C to +200 °C with the temperature of working environment)
• to a way of accession to a pipe (flanges flat, flanges vorotnikovy and carving flnets). Flat flanges put on on a pipe and are welded on a back surface therefore the internal diameter of a flat flange is a little more than outer diameter of a pipe. Vorotnikovy flanges are welded end-to-end, their internal diameter is equal to diameter of conditional pass of a pipe. Carving flanges are applied infrequently.
Requirements to production of flanges very strict. Flanges have to be produced with sealing surfaces of executions 1, 2, 3, 4, 5, 6, 7 and 9 in accordance with GOST 12815-80 of steel of brands 12X18H10T, 08X18H10T, 10X17H13M2 (3)T, etc.
For example, flat flanges at an izgotovleniidolzhna to conform to requirements of GOST 12820-80 and can be applied only in the range of temperature from -70 °C to 450 °C. Flanges steel welded a vstyktakzha have to conform to the state standard specifications 12821-80 standards and be applied in the range of temperature from-253 to 600 °C.